hardworkingstiff
Senior Member
- Location
- Wilmington, NC
Here is the situation.
Conductors are sized using 400.5(B) for W cable feeding power pedestals on floating docks. This has been SOP for years with no problem. The local AHJ does not require engineered drawings.
Now that I have a better understanding of 110.14(C)(1) I know that because of termination limitations, this is not exactly correct (using 400.5(B)).
The load at each power center is (2) 50-amp receptacles with individual meters. So according to 555.12 the calcs are 2*50=100*.9=90.
#4 W (table 400.5(B) at 75C, 2CCC) is rated for 115-amps. #4 (table 316, 75C) is rated for 85-amps. So according to 110.14(C)(1) the #4 is too small.
I really don't have a problem in wiring these power centers with the #4 since it's been done this way for many years with no problems.
The NEC is known to be conservitive on wire ampacities and history says there is no problem. To increase the W cable will cost me the job, so it's do it this way or let someone else do it. The AHJ will not stop it (but I believe it to be because of ignorance). I've been told (by an Electrical Inspector) the strictest local AHJ has turned a blind eye to this for years, but now that's it's spelled out they may start enforcing it.
Here is the input part, if I do this job, am I being too lax?
Conductors are sized using 400.5(B) for W cable feeding power pedestals on floating docks. This has been SOP for years with no problem. The local AHJ does not require engineered drawings.
Now that I have a better understanding of 110.14(C)(1) I know that because of termination limitations, this is not exactly correct (using 400.5(B)).
The load at each power center is (2) 50-amp receptacles with individual meters. So according to 555.12 the calcs are 2*50=100*.9=90.
#4 W (table 400.5(B) at 75C, 2CCC) is rated for 115-amps. #4 (table 316, 75C) is rated for 85-amps. So according to 110.14(C)(1) the #4 is too small.
I really don't have a problem in wiring these power centers with the #4 since it's been done this way for many years with no problems.
The NEC is known to be conservitive on wire ampacities and history says there is no problem. To increase the W cable will cost me the job, so it's do it this way or let someone else do it. The AHJ will not stop it (but I believe it to be because of ignorance). I've been told (by an Electrical Inspector) the strictest local AHJ has turned a blind eye to this for years, but now that's it's spelled out they may start enforcing it.
Here is the input part, if I do this job, am I being too lax?
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